Arrest and Repair of Inflammatory Root Resorption After an Endodontic Regeneration Procedure - A Hypothesis and Case Report.

Introduction: External inflammatory root resorption (EIRR) is a significant complication that can occur following traumatic dental injuries, with a prevalence of approximately 18%. Most cases occur during the early stage of the mixed dentition. Specifically, EIRR occurs in approximately 5%-8% of luxation injuries, 30% of replanted teeth following avulsion, and 38% of intruded teeth. Conventional methods for addressing EIRR in immature teeth pose several challenges. This often requires numerous dental visits where Ledermix and calcium hydroxide are used, which may significantly prolong the treatment. Additionally, the effect of prolonged use of calcium hydroxide medication in the root canal is debatable. Recent publications have highlighted the ability of regenerative endodontic treatment (RET) to effectively stop and repair EIRR in a relatively brief time, yielding impressive results. Nevertheless, the underlying mechanism responsible for this effect remains unclear.

Methods: A hypothesis is proposed and drawn from existing data, explaining the mechanism by which RET triggers alterations in the root dimensions of necrotic immature teeth, facilitating continuous root maturation. The hypothesis suggests that bioactive molecules, including growth factors, might be able to penetrate the denuded dentin, reach the resorbed area, and attract stem cells from the surrounding periodontal ligament and adjacent bone, leading to the arrest of the resorption process.

Results: This recruitment may trigger repair mechanisms, ultimately resulting in the coverage of the denuded dentin with a new layer of periodontal ligament, cementoid, and cementum.

Conclusions: A hypothesis of the potential mechanism in which RET may arrest EIRR is presented along with a case report.